All solid-state secondary battery, solid electrolyte composition, electrode sheet for battery using same, method for manufacturing electrode sheet for battery, and method for manufacturing all solid-state secondary battery

1. An all solid-state secondary battery comprising:

a positive electrode active material layer;

a negative electrode active material layer; and

a solid electrolyte layer,

wherein at least any one of the positive electrode active material layer, the negative electrode active material layer, or the solid electrolyte layer includes a binder made up of an inorganic solid electrolyte having a property of conducting ions of a metal belonging to Group I or II of the periodic table and a high-molecular-weight compound satisfying the following conditions (i) to (iii):

(i) A linking structure of a main chain being constituted of carbon atoms

(ii) Having a repeating unit represented by any one of Formulae (1-1) to (1-3)

(iii) Having at least one of the following functional group set (a)

in the formulae, Z 11 to Z 14 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, two or more of Z 11 to Z 14 may be condensed or bonded together and thus form a ring, Z 15 and Z 16 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group,

functional group set (a) selected from the group consisting of a sulfonic acid group, a phosphoric acid group, a phosphonic acid group, a thiol group, an isocyanate group, and an oxetane group,

wherein, when a functional group selected from the functional group set (a) is an isocyanate group, the repeating unit represented by Formula (2) is contained,

in the formula, Z 21 and Z 22 each are independently a hydrogen atom, a halogen atom, a cyano group, a methyl group, or an ethyl group, Z 23 is a hydrogen atom, a group represented by Z 21 , or a group represented by L 1 -Z 24 , Z 24 is an isocyanate group, L 1 is a single bond, or a hydrocarbon linking group, O, NR N , CO, or a linking group obtained by combining any of these linking groups, R N is a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, or an aryl group,

wherein a weight-average molecular weight of the high-molecular-weight compound forming the binder is 15,000 to 1,000,000, and

wherein, in the high-molecular-weight compound for forming the binder, a content of the repeating unit represented by any one of Formulae (1-1) to (1-3) in a molecule is 80% by mass or more.

2. The all solid-state secondary battery according to claim 1 ,

wherein the L 1 in Formula (2) is a hydrocarbon linking group, O, NR N , CO, or a linking group obtained by combining any of these linking groups.

3. The all solid-state secondary battery according to claim 1 ,

wherein Z 11 to Z 14 each are independently a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, or an aryl group having 6 to 22 carbon atoms.

4. The all solid-state secondary battery according to claim 1 ,

wherein Z 15 and Z 16 each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkynyl group having 2 to 6 carbon atoms.

5. The all solid-state secondary battery according to claim 1 ,

wherein the group selected from the functional group set (a) is selected from a sulfonic acid group, a phosphoric acid group, and a phosphonic acid group.

6. The all solid-state secondary battery according to claim 1 ,

wherein the inorganic solid electrolyte is an oxide-based inorganic solid electrolyte.

7. The all solid-state secondary battery according to claim 6 ,

wherein the inorganic solid electrolyte is selected from compounds of the following formulae:

Li xa La ya TiO 3

in the formula, 0.3≤xa≤0.7 and 0.3≤ya≤0.7

Li xb La yb Zr zb M bb mb O nb

in the formula, M bb is at least one element of Al, Mg, Ca, Sr, V, Nb, Ta, Ti, Ge, In, or Sn, 5≤xb≤10, 1≤yb≤4, 1≤zb≤4, 0≤mb≤2, and 5≤nb≤20

Li xc B yc M cc zc O nc

in the formula, M cc is at least one element of C, S, Al, Si, Ga, Ge, In, or Sn, 0≤xc≤5, 0≤yc≤1, 0≤zc≤1, and 0≤nc≤6

Li xd (Al,Ga) yd (Ti,Ge) zd Si ad P md O nd

in the formula, 1≤xd≤3, 0≤yd≤1, 0≤zd≤2, 0≤ad≤1, 1≤md≤7, and 3≤nd≤13

Li (3-2xe) M ee xe D ee O

in the formula, xe represents a number of 0 to 0.1, M ee represents a divalent metal atom, and D ee represents a halogen atom or a combination of two or more halogen atoms

Li xf Si yf O zf

in the formula, 1≤xf≤5, 0≤yf≤3, and 1≤zf≤10

Li xg S yg O zg

in the formula, 1≤xg≤3, 0≤yg≤2, and 1≤zg≤10

Li 3 BO 3 —Li 2 SO 4

Li 2 O—B 2 O 3 —P 2 O 5

Li 2 O—SiO 2

Li 6 BaLa 2 Ta 2 O 12

Li 3 PO (4-3/2w) N w

in the formula, w is w<1

Li 3.5 Zn 0.25 GeO 4 having a LISICON-type crystal structure

La 0.55 Li 0.35 TiO 3 having a perovskite crystal structure

LiTi 2 P 3 O 12 having a NASICON-type crystal structure, Li (1+xh+yh) (Al, Ga) xh (Ti, Ge) (2-xh) Si yh P (3-yh) O 12

in the formula, 0≤xh≤1, and 0≤yh≤1

Li 7 La 3 Zr 2 O 12 having a garnet-type crystal structure

lithium phosphate

LiPON obtained by substituting some of oxygen atoms in lithium phosphate with nitrogen

LiPOD 1

in the formula, D 1 is at least one selected from Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Mo, Ru, Ag, Ta, W, Pt, or Au

LiA 1 ON

in the formula, A 1 is at least one selected from Si, B, Ge, Al, C, Ga, or the like.

8. A solid electrolyte composition applied to an all solid-state secondary battery comprising:

a binder made up of an inorganic solid electrolyte having a property of conducting ions of a metal belonging to Group I or II of the periodic table and a high-molecular-weight compound satisfying the following conditions (i) to (iii):

(i) A linking structure of a main chain being constituted of carbon atoms

(ii) Having a repeating unit represented by any one of Formulae (1-1) to (1-3)

(iii) Having at least one of the following functional group set (a)

in the formulae, Z 11 to Z 14 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, two or more of Z 11 to Z 14 may be condensed or bonded together and thus form a ring, Z 15 and Z 16 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group,

functional group set (a) selected from the group consisting of a sulfonic acid group, a phosphoric acid group, a phosphonic acid group, a thiol group, an isocyanate group, and an oxetane group,

wherein, when a functional group selected from the functional group set (a) is an isocyanate group, the repeating unit represented by Formula (2) is contained,

in the formula, Z 21 and Z 22 each are independently a hydrogen atom, a halogen atom, a cyano group, a methyl group, or an ethyl group, Z 23 is a hydrogen atom, a group represented by Z 21 , or a group represented by L 1 -Z 24 , Z 24 is an isocyanate group, L 1 is a single bond, or a hydrocarbon linking group, O, NR N , CO, or a linking group obtained by combining any of these linking groups, R N is a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, or an aryl group,

wherein a weight-average molecular weight of the high-molecular-weight compound forming the binder is 15,000 to 1,000,000, and

wherein, in the high-molecular-weight compound for forming the binder, a content of the repeating unit represented by any one of Formulae (1-1) to (1-3) in a molecule is 80% by mass or more.

9. The solid electrolyte composition according to claim 8 ,

wherein the L 1 in Formula (2) is a hydrocarbon linking group, O, NR N , CO, or a linking group obtained by combining any of these linking groups.

10. The solid electrolyte composition according to claim 8 , further comprising:

a dispersion medium.

11. The solid electrolyte composition according to claim 10 ,

wherein the dispersion medium is selected from alcohol compound solvents, ether compound solvents, amide compound solvents, ketone compound solvents, aromatic compound solvents, aliphatic compound solvents, and nitrile compound solvents.

12. The solid electrolyte composition according to claim 8 ,

wherein a content of the binder is 0.1 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the inorganic solid electrolyte.

13. The solid electrolyte composition according to claim 8 , further comprising:

a positive electrode active material.

14. The solid electrolyte composition according to claim 8 ,

wherein the inorganic solid electrolyte is an oxide-based inorganic solid electrolyte.

15. An electrode sheet for a battery obtained by forming a film of the solid electrolyte composition according to claim 8 on a metal foil.

16. A method for manufacturing an electrode sheet for a battery, comprising:

forming a film of the solid electrolyte composition according to claim 8 on a metal foil.

17. A method for manufacturing an all solid-state secondary battery, comprising:

manufacturing an all solid-state secondary battery by way of the method for manufacturing an electrode sheet for a battery according to claim 16 .